Disable resilience for modules imported by the MemoryBuffer loader.

The MemoryBuffer loader is used by LLDB during debugging to import binary Swift
modules from .swift_ast sections. Modules imported from .swift_ast sections are
never produced from textual interfaces. By disabling resilience the expression
evaluator in the debugger can directly access private members.

rdar://79462915

include/swift/AST/Module.h

@@ -257,6 +257,9 @@ private:
 
   AccessNotesFile accessNotes;
 
+  /// Used by the debugger to bypass resilient access to fields.
+  bool BypassResilience = false;
+
   ModuleDecl(Identifier name, ASTContext &ctx, ImplicitImportInfo importInfo);
 
 public:
@@ -290,6 +293,12 @@ public:
   AccessNotesFile &getAccessNotes() { return accessNotes; }
   const AccessNotesFile &getAccessNotes() const { return accessNotes; }
 
+  /// Return whether the module was imported with resilience disabled. The
+  /// debugger does this to access private fields.
+  bool getBypassResilience() const { return BypassResilience; }
+  /// Only to be called by MemoryBufferSerializedModuleLoader.
+  void setBypassResilience() { BypassResilience = true; }
+
   ArrayRef<FileUnit *> getFiles() {
     assert(!Files.empty() || failedToLoad());
     return Files;